Method of making pinking shears cutters



April 28, 1953 s. sHALER 2,636,402

METHOD OF MAKING PINKING SHEARS CUTTERS Filed June 30, 1950 2 SHEETS-SHEET l FLE 4.

BY @mda ATTORNEY April 28, 1953 S. SHALER MAKING P METHOD OF INKING SHEARS CUTTERS 2 SHEETS INVENTOR 5610/. SH@ 5g Patented Apr. 28, 1953 OFFICE METHOD OF MAKING PINKING SHEARS CUTTERS Saul Shaler, Jackson Heights, N. Y.

Application June 30, 1950, Serial No. 171,467

claims. (c1. irs-104) :This invention relates to the manufacture of pinking shears and more particularly to the provision of efficient cutting edges on such shears.

In pinking shears the cutting is accomplished by two blades, the cutting edges4 of which are complementarily serrated so that, as the blades are brought together with a shearing action, the successive teeth of the two blades pass through one another in a complementary manner and in mesh. In order to cut properly, the teeth of each blade must accurately intert with the corresponding spaces between teeth of the other blade, with the coasting edges of the respective teeth keen and close fitting. If the teeth do not properly interfit with one another or the edges are not keen, the fabric to be cut will be drawn or torn rather than cleanly cut.

The problem of producing properly intertting keen edged teeth has long been a serious manufacturing problem in the making of pinking shears. The most commen methods of obtaining accuracy, within fair operating limits has been to mill or broach the teeth and thereafter lap them, care being taken to fit individual pairsof blades for proper cooperation with one another. This prior practice is expensive and requires a high degree of skill and accurate machinery, grinding wheels, etc., and the operations must be painstakingly performed.

The primary object of the present invention is to provide a simple and economi-cal method of producing sharp and accurate teeth by quantity production and without requiring the fitting of matched pairs of blades.y The present invention makes it possible :to manufacture these blades in bulk and thereafter assemble any two v blades thus made and yet obtain keen intertting cooperation in the end product shears.

In practically carrying out the invention in its preferred practical form, I preferably blank out each of the blades from flat sheet metal stock. During the blanking operation, the serrated edges which are to form the teeth are cut with the serrated edges of the teeth normal to the plane of the blank. The edge of the blade along which the serrationsare formed is thereafter upset, so

that the serrations are positioned along the free edge of a marginal -cutting flange.l This marginal cutting ange is arranged in angular relation to the longitudinal medial line of the blade so that, when two blades are brought into cooperation in a shears, the flanges will be arranged in diverging relation, whereby the teeth longitudinally of the two blades'successively coact as the shears are operated. i

` It is preferred that the blades move toward on another to effect the cutting in a direction substantially normal to the longitudinal medial lines of the two blades,v i. e., that the blades partake of substantially parallel movement toward and away from one another. Inasmuch as the teeth are blanked with the sides of the teeth normal to the faces of the iianges, it is apparent that the teeth of two blades so mounted and operated cannot properly mesh. I therefore recut at least one side of each tooth of each blade, so as to permit the teeth of the two blades to successively pass .through one another. This cutting is in the nature of a shaving operation, wherein at least one edge of each tooth is shaved away ba-ck of the leading edges of the teeth. The shaving operation is preferably so performed as to not materially change the shape of the cutting edges of the teeth, but to give clearance back of such cutting edges, as hereafter more fully described. If the flanges of the cutting edges are thereafter ground fiat and the cutters hardened, the teeth will be provided with sharp cutting edges with adequate clearance.

Features of the invention, other than those adverted to, will be apparent from the hereinafter detailed description and claims, when read in conjunction with the accompanying drawings.

The accompanying drawings show consecutive steps in carrying out the invention in its preferred form, but the particular structures therein illustrated are to be understood as illustrative only and not as defining the limits of the invenion.

Figure 1 is a face View of a pinking shears, the blades of which may be accurately made according to the present invention. 1

Figure 2 is a section on the line 2 2 of Figlire 1.

Figure 3 graphically illustrates the relative divergent relation between the cutting teeth of the two blades of Figure l and the manner in which the teeth are cut according to the present invention.

Figure 4 is a fragmental side elevation of one of the serrated edges shown in Figure 3, showing in like manner the different cuts by which such edges are formed.

Figure 5 is a fragmental section on the line 5 5 showing the relation of the teeth as illustrated in Figure 2, both before and after the shaving cuts to which I have referred.

Figure 6 is a section of a shaving die couple useful in carrying out the present invention, this section being taken on the line 6.-6 of Figure 7.

Figure '7 is a transverse section on thev line 'l-l of Figure 6.

While the present invention may be employed in connection with pinking shears of different design, I have chosen, for the purpose of illustration, to show the same as employed in the making of pinking shears such as disclosed in my application for United States Letters Patent, Serial No. 149,921, filed March 16, 1950, Self Adjusting Pinking Shears. Such a pinking shears is shown in Figure l of the drawings. It comprises a. pair of blades I mounted for operation upornlevers 2,.,and 3 proyidedirithmandles 4 and Sian'diiadpted to impartitotthelbladcsa substantially parallel movement' toward and away from one another.

The blades I are made from sheet metal with right angular flanges 6, alongrthereeiiegesf which are formed serrations constituting teeth 1. The blades are so made and..mounted that the flanges `B are arranged in diverging^relaticn to one another, aas shown inz'fkigimelitandawhie the angle of divergence a may vary within con- `sderable limits, we will assume for ther-present 'description that this angle is 15 degrees. The

fipnmosemfithe divcrgingrrows oftteetheisitof-inrsureLth-atiat Lleastzxoneitoeth :ofstthelibladeaisin ::mesirwithxcorrespcnding-teeth;oisthe v'ether blade zsiatzallstimes. ,-Ltsrthe'handlesillvandi5areoperatetl,

ianother to ,successively 1s mesh the fiteeth. 'j @his @movement inl-:the direction substantially mcr- -ssmalitd aslineflb hisectingflthexanglezofzxiivergence. f;".f'fh.is.isquecnliarztothefshearszshowniineFigure'l,

arditi-longhitheemovementrothe bladesatoward'fone i.sarrother:nriay.` differ .from ythe rectilinear-immetmentrreerred to xand'rstillasheiinvention@stuseaulniniconjnnction therewith. ;.;.:In;:iaccerdance :with 'athe- 'fmethodxx of' ffthis; :in- --avention-,iieach of? theiblades i L-.and z 2 'fiblankedi from 1flatrsheetvmetaLstockiama-during l1 hianking'foperationithefedgesi ofithefblades :tare sserratedfltorformrtheiteeth T1. "These teeth lare cut fairly accurate and uniformfandfof'fsubestantially.etica.meptlfrcanti fpitchf that whey-*twill f.

"shavein'itheierrcliprorisuctrshears. .'Thefstamping :ifisxaccomplishedzn .iaidirection 'rnormal to c@the faceidf. the blankf-randcconsequently the: 'cli-verging '.'fedgesofnfthezteethfwillfbe lcutrsubstantial'ly finorl:malto itheitacefof:the-blank. QALftcr the 'biank @dias-in eenzfproduced=,:as stated gfthei-toothedf or--sern"ratedizmargirrithereof:is' upset to fformithe=fiiange --rxwhiehsezitends,latxrightfangles .to the remainder 'of the blade. If two blades thus iormedware -Qincorporatedz @theI-shearsfshoWn-.in iignre 1, ffthetrelation ofi'thesteeth"ofnsuchfbladesf willtapvpear from Figures -,fif-and.

.fBy .i reference 1tc i Figurei3 particular, e the relatively heavy full lines indicate the crowns aandv svalfieysrfrthefycriginal blanking "cute fofthe -titee'tthsxandA are Edesignatedfbyfthefreferenti@ char- A-taie'zterl iti-:thisigureraridin'theiFiguresfl/lvand. ,Strietlynfspeaking' theserheavylines ll-woiildffnot vshovv in the upper blade as it appears ig butfi'have illustrated-theminy tliisrwayin the finterest' ot' elearness dfFremi this Figure 13,- it is =per-eetiy "clear` that the two flanges 6 shown in this'gnrefcoldfnot ^-fpos'sibiy-be= lirioved towardfone @another in a diereetion norma'lto ftherplane o-therbise ctingline "fvb toca-use 'the teeth of-fone ange'to pass through or meshfltvith'f'the teeth oithe other. "heiin- Lfelination of f the lines-Y il `2demonstrate `that lsuch *sani-@operation would --be impossibieffor 'in this 4 figurethe angle'ioi divergence yof 'fthe -'flanges'- is 'vapproXimateiyi5, withamaneleioi 'l/z'ateach side of the bisecting line b.

"ffnfforder 'to permit zthese teeth to meshA and VV,rpasswhen thusmoved Subj ect tbeg-lge fof fea'chfblade3to a shavingmoperation ,Thisjshav- ""iingoperation may, if desired; bel'in; a Ydirection i normatto the plane'iofztlie. bisectingfline't and, ff 'ifthusg performed; it .would suilstantiallyA kparallel fthe yfaces of vvvthe :corresponding lteeth ,of ".b'oth l"f'fianges esc that theyowold'pass Lthrough "and ...l0 Thisjmay `be accomplished, in the illustrative "*formfrtheinvention shown, by supporting the :Lt-bladesosthati-itstlength will be inclined at, for

example, 8l to the horizontal. At the same time thefblad'e is supportedso that the fiange Ethereof is tilted up slightly, as shown in Figure '1, so athen-initialiser tilts umvardivifrnm:theixoritcntal mianettotvardiiitseserratededge 'Lata-fan 1ariglerof e. 4'5- .vtostheizhcrizontaL fWhileiliheme-S A @this comneundaaneleofi-inclinationiand .-it1lt.iact eport. .the bladexby afsiiavineutter cna #whichiiwillmreferabl leaves-'the uitweg-.edges auofithe teethilruntoiichedizbutewil Islraweiftlule :sidestofether teeth mvithcfaftarerinetcut finzardcwnmardi direction :toimndercut @the dvrgnga edges of y:the :teeth loci-.heini al idirectiennlangtudinaliy aci .the manges-.and innfafidirection ktraiteralately "cthereei 'sftiresifL 4,;-andg5irshowivery olcarlythereult 'scf fthisseperation, ther-shaving cuts hcingmnade .fa ngcthegheaityedcttedilinesQeinztheseismes eine steek;rtlmsl remevewwill- :be enmarca-aine thickness in atdirectioneawayffnomi.. her-.cutting eenige producingithe::undercutiiliustrated in i-rettecl,vlines'fin these insures.;iv Bymthusnunrlercutyltinigthebteeth.. in:a directionzawayifromrthefcutiatingaedges, ntheseicuttingiedgesmf :the teethware 'snot xoniyitrued-.rbutclearanceisaprovdediback lof 'said :cutting tedges. When these .teeth'r pass `i.tl-arc,ugltr.:me :another ".inizthe. assembledimanner 4o for Figiire.: Lathe cutting-edgesWillijtheoreticaily f contact .withfoneianother ithrouehmititheir entire Ytesitentifioutbaciaeiithese cuttingfedgessithetteeth will nctifengage. Y.'hisuvviilaproducei cieanance. as-

suring the most emcientvciittingmfftabrics and l 'ether'- :materialsA Without afdrag.: or ttearngeiaction io-.rename goods.

'.praeticaliyf: carryingeontezthis 'i:ieventim;s"v I Amrray eut eawayf'itlaexentire 1amfount-trifa=material 'ui'flf'rieiifit-isz-desired tofremcve lay-agshavingmperz-aticn'lin onefs'teppaltlnoirgli itmaywbe aeccinplislfred "0- 'lf-by tstagesmbodying-ta @successioni ef @thinner -70 treated to harden the teetliso ,that theyzrvilrnot -75 fabrics *including-inesilkrrayons -andrniflona The teeth are, moreover, suiciently rugged to properly back up the cutting edges 6a, so as to permit the use of the shears in the cutting of relatively heavy fabrics, such as overcoat fabrics and the like.

In the carrying out of this invention, I may use apparatus of widely different character. However, for the purpose of illustration, I have shown shaving dies and their cooperating parts in Figures 6 and 7. In these figures It designates a shaving die, mounted on a vertical reciprocating head I i toward and away from stationary bed carrying a stationary supporting die i3. The blade l is shown in these figures as held, by a spring pressed holder lil, in engagement with the stationary supporting die 3. Figure 6 shows that the blade is so held inclined at an angle of approximately 8 to the horizontal in the direction of its length and the teeth 7 of the flange are shown as they are originally blanked. They have not yet been shaved. In Figure 7, the tilted position of the fiange is apparent, this tilt being shown at approximately 4.

in the apparatus of these figures, the descent of the shaving die l will cause the teeth l to be shaved and undercut, as hereinbefore described, the part i of these figures constituting a back-up block which moves downwardly with the shaving die to properly back up and support the blade while the shaving cut is made. This back up part i5 is shown as mounted on the head ll by screws it passing through slots i? to permit shifting of the back up part i so that it may be kept in contact with the blade by an abutment i8 on a stationary guide as the shaving die descends.

The foregoing detailed description sets forth the blanking of sheet metal with the blanking die moving normal to the face of the sheet so as to cut the teeth in a direction normal to such face. If desired, however, I may move the blanking die at an angle to the face of the sheet so as to cut these teeth on a slight angle instead of normal to the face of the sheet as stated. In that case, I thereafter shave the teeth, as hereinbefore described, to give clearance and sharp cutting edges.

Also I may blank out the blade without necessarily cutting the teeth during the blanking op eration and cut the teeth by a separate operation after the blank has been formed. In this flatter case, the teeth may be formed either before or after upsetting cutting flange of the blade. These modification steps are included in this invention.

In accordance with the present invention, it is possible to finish all work on the blade beforethe hardening step so that the hardening step is the last step in the manufacture of the blade. This makes it possible to more readily manipulate the material of the blade and effect the blanking and shaving operations of its manufacture and nothing needs to be done thereon after a final hardening step. So far as I am aware, this is a novel feature in the making of cutting blades for pinking shears.

From the foregoing disclosure the marked sirnplicity of the method of the present invention will be apparent. The necessity of milling and lapping of matched blades is entirely unnecessary when the present invention is practised. Blades may be expeditiously produced by this method and used interchangeably as rights and lefts in quantity production of shears of the character illustrated in Figure 1. Every operation involved in the method of this invention is a simple operation to be carried out by unskilled help. So long as the dies are properly made, the end product will be uniform and satisfactory performance of the end product shears is assured.

The method of this invention because of its simplicity makes quantity production possible and A not only very materially reduces the cost of production of pinking shears, but insures a very more efficient cutting operation.

The foregoing detailed description sets forth the invention in its preferred practical form, but the invention is to be understood as fully commensurate with the appended claims.

Having thus fully described the invention, what I claim as new and desire to secure by Letters Patent is:

1. The method of making a pinking shears cutter blade which comprises-z blanking a blade from sheet metal stock with cutting teeth along one of its free edges, and thereafter rectilinearly shaving the cutting faces of the teeth at a compound angle to provide clearances when two such blades are operated in a pinking shears.

2. Method as claimed in claim 1, wherein the cutting face of the blade is subsequently ground to render keen the cutting edges of the teeth.

3. The method of making a pinking shears cutter blade which comprises: blanking a blade from flat sheet metal stock with serrated teeth along one of its edges, thereafter upsetting the toothed margin of the blade to form acutting flange carrying the teeth, and thereafter simultaneously rectilinearly shaving both sides of said teeth at angles to both the length and width of the fiange.

4. Method as claimed in claim 3, wherein the cutting face of the flange is subsequently ground to render keen the cutting edges of the teeth.

5. The method of making a pinking shears cutter blade which comprises: forcing a die through metal stock in a direction substantially normal to the face of the stock to form a blade blank with a succession of cutting teeth along one margin thereof, and thereafter simultaneously rectilinearly shaving both Y'sides of said teeth at angles to both the length and width of the blade.

SAUL SHALER.

References Cited in the le of this patent UNITED STATES PATENTS Number Name Date 57,205 Sowden Aug. 14, 1866 489,405 Austin Jan. 3, 1893 567,295 Coursen Sept. 8, 1896 1,959,190 Wyner et al May 15, 1934 2,204,071 Dalley June 11, 1940 2,284,664 Kissling June 2, 1942 2,286,874 Schwartz June 16, 1942 2,290,203 Nikonow et al. July 21, 1942 2,501,718 Gillette Mar. 28, 1950 2,508,706 Cohn May 23, 1950 2,511,187 Weidauer June 13, 1950 2,565,552 Ern Aug. 28, 1951 2,579,521 Sorensen Dec. 25, 1951 FOREIGN PATENTS Number Country Date 424,807 Great Britain Feb. 28, 1935 

